George Zimmerman talks to his attorney, Mark O'Mara, during a recess in Seminole circuit court on the sixth day of his murder trial June 17 in Sanford, Fla. / Pool Getty Images

by Yamiche Alcindor, USA TODAY

by Yamiche Alcindor, USA TODAY

SANFORD, Fla. - A neighbor of George Zimmerman testified Friday that it appeared that teenager Trayvon Martin was striking Zimmerman while straddling him moments before the teen was shot.

Jonathan Good, who lives in the same townhouse complex as Zimmerman, said after hearing a noise behind his townhome, he saw what looked like a fight. When he stepped outside, he said he yelled, "What's going on? Stop it."

"It looked like there were strikes being thrown, punches being thrown," said Good.

Good said he could only see one person at first. Seconds later, he saw two people laying flat, one on top of the another in the grass. A person in dark clothing was on top of a person with a "lighter complexion" wearing red or white clothing, Good said. The description of the person on the bottom, Good said, matched Zimmerman that night. The person on the top had similar dark clothing as that worn by Trayvon, he said.

Zimmerman, 29, is on trial for second-degree murder for the February 2012 shooting death of Trayvon, 17. Zimmerman, who has pleaded not guilty, has said that he acted in self-defense after he was attacked.

Trayvon's death and the speculation that Zimmerman, who is Hispanic, profiled, followed and murdered him sparked racial controversy and protests around the country last year. Zimmerman, who faces life in prison if convicted, has maintained that race did not factor into his actions.

Under cross-examination by defense attorney Mark O'Mara, Good testified that during the tussle, the teen appeared to execute a mixed-martial arts maneuver known as"ground and pound."

"I only saw downward movements," Good said, when pressed for details about what Trayvon's arms were doing right before he was killed.

Good testified that he heard one or two calls for "help" and thought the words came from Zimmerman. Good said he did not see actual blows between the two, however. Good said he was dialing 911 when he heard a gunshot.

Good's version of that night contradicts those of another neighbor who testified Thursday. Selma Mora, who lived a couple of houses down from Good, said a person straddling on top of another person told her to call police. Minutes later, the same person who was on top, Zimmerman, was on his feet after a gunshot, Mora said.

Jonathan Manalo, whose wife testified earlier this week, told jurors he was the first person to make contact with Zimmerman after the shooting. He described Zimmerman as calm and easy to understand before police arrived. Manalo said as soon as he saw Zimmerman, Zimmerman started explaining what happened.

"I was defending myself when I shot him," Manalo said Zimmerman told him. Soon after police arrived and Zimmerman asked Manalo to call his wife. "Just tell her I shot someone," Manalo said Zimmerman told him.

State prosecutors also called two Sanford Police officers and an emergency medical technician to testify about the scene, Trayvon's body position, and Zimmerman's injuries. EMT Stacy Livingston testified that Trayvon was unresponsive and had no pulse. He was pronounced dead at 7:30 p.m. the night of the shooting, Livingston told jurors.

Livingston also testified that she treated Zimmerman, who had a swollen nose and bloodied face. She also cleaned two lacerations on the back of his head.

Officer Timothy Smith, who handcuffed Zimmerman and took his gun away, said Zimmerman twice offered an explanation for the shooting while being transported to jail.

"He stated to me that he was yelling for help and nobody came to help him," Smith testified.

Zimmerman also looked confused and told Smith he was light headed, but that he didn't want to go to the hospital, Smith said. While handling Zimmerman, Smith noticed that the back of Zimmerman's jacket and pants were wet and had grass blades on them. The moister indicated that Zimmerman "had been laying on his back," Smith said.

Lindzee Folgate, a physician assistant who had treated Zimmerman previously, said she treated him a day after the shooting. Zimmerman told her he had been in a fight and shot someone. She said Zimmerman said he was stressed and got nauseous when he thought about the shooting.

Asked about his injuries, Folgate said Zimmerman's nose appeared to be broken and his head had several cuts. She also told the jury Zimmerman's injuries could have been caused by head trauma including having his head slammed into concrete as he has claimed. Folgate, however, added that the cuts did not require stitches and that she suggested Zimmerman get pain medication and seek massages for treatment.

Zimmerman had been "intensely" involved in mixed martial arts three days a week in August 2011, she said. Zimmerman had problems sleeping and falling down and got involved in mixed martial arts to treat his issues. The exercising didn't work, however, and Zimmerman sought medical treatment for his ailments, Folgate said.

Folgate said after seeing Zimmerman a day following the shooting, she recommended Zimmerman, who was already "established" with a psychologist, see a psychologist and an ear, throat and nose doctor.

The physician's assistant was the last witness to testify before the trial was adjourned until Monday.